Chevron - the Northern California-based oil and gas company – has been quietly acquiring rights to drill for natural gas in Eastern Europe using “fracking” technology – a controversial technique. However, grassroots opposition in Bulgaria and Romania has thwarted the companies plans so far.

An interview with Ian MacDonald, vice-president of Chevron Europe, Eurasia and Middle East, in the Financial Times suggests that the company is getting ready for what it believes is the next fossil fuel extraction boom in the region.

But the company faces an uphill political battle to the technology that has been blamed for contaminating local water supplies and even causing earthquakes. Bulgaria banned fracking in January after a major protest against Chevron’s plans to drill in Dobrudja, the most fertile farm region in the country in January.

Chevron is also running into fierce opposition in Romania which has a moratorium on the technology. The company has licenses in the north-east and south-east Dobrogea region near the southern border with Bulgaria as well as for the in north-eastern Romania near the border with Moldova.

“The fracturing of a single well requires a huge volume of water: around 9,000 - 29,000 m3 (9 -29 million litres). Chemicals make up about 2% of the fracturing liquid, i.e. about 180,000 – 580,000 litres. Only 15 – 80% of the injected fluid is recovered, meaning that the rest remains underground, where it is a source of contamination to water aquifers.”

The contamination has shown up in unusual place. For example communities in the U.S. have seen tap water catch on fire in fracking areas. (Watch this YouTube video and this one from Time magazine)

A new study from Cliff Frohlich, a seismologist at the University of Texas, Austin, just published in the Proceedings of the National Academy of Sciences, shows a high degree of correlation between local earthquakes and fracking. “Beginning in 2001, the average number of earthquakes occurring per year of magnitude 3 or greater increased significantly, culminating in a six-fold increase in 2011 over 20th century levels,” Frohlich wrote. “This suggests injection-triggered earthquakes are more common than is generally recognized.”